The term network device generally refers to a class of electronic appliances (e.g., hubs, switches, routers, etc.) that facilitate the communication of data (e.g., in packet form) within and between networks from a source computing appliance to a target computing appliance. One type of network device is a router.
Simplistically, a router is comprised of a number of interface ports, coupled with one or more network processor(s) through a high-bandwidth router switching fabric. Packets received at an interface port are switched to an available network processor, which analyzes the packet header to identify the target computing appliance and select a next hop (i.e., next node) in the network infrastructure to the target computing appliance.
Network devices (e.g., routers) are typically implemented using an extensible rack-mounted chassis. The chassis is comprised of a number of slots, to receive one or more network processor boards, switching boards, telco I/O boards, etc. The boards are communicatively coupled to one another through a backplane to which each of the boards is coupled.
One of the limitations commonly associated with such network devices is that they are application specific. A router, for example, typically only performs routing tasks, i.e., analyzing a packet header for destination information, analyzing a router table to correlate the identified destination with a next hop, and forwarding the packet to the identified next hop towards the target destination. Network devices are not designed for, and typically do not perform additional processing tasks extraneous to the task of moving packets from source to destination.
With the advent of streaming media, the amount of media content that is now traversing otherwise traditional data networks continues to grow, although still a small subset of the overall traffic traversing the network. Once the province of high-end desktop computers, media content is now accessed by any number of clients including handheld devices (e.g., personal digital assistant (PDA), palmtop computers, wireless telephones, etc.), laptop computers, and the like. Such a broad range of computing appliances has an associated range of computing power that can be brought to bear on processing media content, some of which are up to the task, while others need processing assistance to meet the expectations of the user.
Consequently, there is a need to support the delivery of such media content to/from a heterogeneous client-base, while expanding the scope of services for traditional data networks and network devices.